Method for insulating a surface

ABSTRACT

A method is provided for sealing and/or insulating a construction surface. Foam is applied to the construction surface followed by insulating material. The foam mechanically couples to the construction surface, and the insulating material mechanically couples to the foam. Alternatively, a structure is provided having a construction surface. A foam layer is adjacent to and mechanically coupled to the construction surface. Insulating material is adjacent to and mechanically coupled to the foam layer.

RELATED APPLICATIONS

[0001] This application claims benefit of U.S. application Serial No. 60/322,349, filed Sep. 14, 2001 and entitled “Method For Insulating A Surface,” which is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to the application of insulating layers to the inside walls, ceiling, and/or floor of various spaces, including in particular limited access or non-residential spaces. More particularly, the present invention relates to the use of a spray polyurethane foam as an adhesive to support insulating bats on walls and ceilings.

BACKGROUND

[0003] It is often desirable to provide climate-controlled air in various limited-access or non-residential spaces, such as attics, storage areas, or other spaces that are typically uninhabited. A primary step in providing such climate control is the reduction of heat transfer between the space and the outdoors. Typically, in an attic or similar space, the structural components of the walls, ceiling, and/or floor, such as roofing materials, are not designed to provide any significant thermal insulation. Hence, it is often desirable to add an insulating layer to the unfinished inside surfaces of the walls and/or ceiling and/or floor of such spaces. For convenience, these surfaces are hereinafter referred to as the “construction surface.” It is often considered desirable to also provide an air and moisture seal between the inside space and the outdoors.

[0004] It is known that rigid, spray polyurethane foams provide good thermal insulation and can function as effective air and moisture seals if properly applied. However, such foams are typically relatively expensive when compared to other types of thermal insulation. Hence, it is desirable to provide a method for insulating and sealing certain spaces without incurring unnecessary expense.

[0005] Since the spaces in question are not intended for normal residential habitation purposes, the applicable fire codes that govern the construction of such spaces are different from the fire codes that govern inhabited residential spaces. Often, the codes are such that it is neither necessary nor economical to provide a thermal barrier such as sheetrock or a cementitious layer. Thus, when homes or other buildings are built to municipal codes specifications, such spaces are typically not insulated or sealed, nor are they designed to allow for easy application of insulation later. Therefore, it is desirable to provide a method for insulating construction surfaces that were not originally designed for installation of insulation or for sealing.

SUMMARY OF THE INVENTION

[0006] An embodiment of the present invention provides a method for insulating a construction surface. A foam is applied to the construction surface such that a foam layer is formed on the construction surface. Insulating material is then applied to the foam such that the insulating material engages the foam layer and is mechanically supported thereby. In an alternate embodiment, a foam layer is formed on the construction surface, and an insulating material is pressed into engagement with the foam layer such that it mechanically couples to the foam layer.

[0007] Another embodiment of the present invention provides a method for sealing a construction surface. A polyurethane foam is applied to a construction surface such that a foam layer is formed on the construction surface. A bat of insulating material is engaged with the foam layer such that the bat is mechanically coupled to the foam layer and supported thereby.

[0008] Another embodiment of the present invention provides a building. The building has a construction surface with a side. A polyurethane foam layer is adjacent to the side of the construction surface and is mechanically coupled to the construction surface. An insulating layer is mechanically coupled to the foam layer.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] For a more detailed understanding of the invention, reference will be made to the accompanying Figures, wherein:

[0010]FIG. 1 represents one embodiment of the present invention. The Figure shows a construction surface with foam layer applied and with insulating material being applied;

[0011]FIG. 2 represents another embodiment of the present invention. This embodiment comprises an optional layer applied to the construction surface prior to application of the foam layer;

[0012]FIG. 3 represents another embodiment of the present invention in which the foam layer covers less than the entire construction surface; and

[0013]FIG. 4 represents a structure wherein one wall contains an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0014] It has been discovered that an effective and economical sealing and insulating layer for a portion of a residential space or other structure can be formed by applying a first layer of sprayed, rigid polyurethane foam and a second layer comprising insulating glass fiber or mineral wool bat. In a preferred embodiment, the bat is applied before the end of the rise period, so that the outer fibers of the bat are incorporated into the outermost portion of the foam layer. In this manner, the bat is mechanically bonded to the foam layer.

[0015] Thus, the present invention provides a method for insulating and/or sealing a space. The space may be a typically uninhabited area of a residential dwelling, such as a storage area or attic, or it may be any area in a commercial structure. The method may be applied in any area having a sufficiently rigid wall, floor, ceiling, or other structure that is to be sealed or insulated. For simplicity, the surface to be sealed or insulated—including a wall, floor, ceiling, or other structure to be sealed or insulated—will be referred to as the “construction surface.” The construction surface may be supported by wood, metal or some other material, and it may be smooth or interrupted by structural members. The construction surface may or may not be originally designed to support insulating material. Also, the construction surface may be a barrier between an inside area and an outside area, or it may be a barrier between two inside areas.

[0016] To perform an embodiment of the method, a foam is applied to the construction surface such that it forms a foam layer adjacent to and engaged with the construction surface. In one embodiment, the foam layer substantially covers the construction surface and provides sealing and insulation for the construction surface. An insulating material is applied to the foam layer such that the insulating material engages the foam layer and is mechanically coupled to the foam layer providing further insulation to the construction surface. The insulating material may be applied in bats or other forms such that it substantially covers the foam layer.

[0017] The present invention also provides an insulating structure. The insulating structure is composed of a construction surface. A foam layer is mechanically bonded to the construction surface, and an insulating material is mechanically bonded to the foam layer. The foam layer may completely cover the construction surface for sealing purposes, or it may cover less than the full construction surface. The insulating structure may be part of a larger structure such as a building, including residential, commercial, or any other type of shelter.

[0018]FIG. 1 illustrates one embodiment of the present invention. The construction surface 10 may be a wall, floor, ceiling, or other boundary of any substantially enclosed space. The space may be a room in a residential structure such as an attic or any other attached room. The space may also be a stand-alone structure, or it may comprise part of or a whole commercial structure. The construction surface 10 may be any boundary of any structure for which insulation or sealing is sought. The construction surface 10 may be composed of wood, metal, a combination of wood and metal, or any other commonly used structural material, as is known to one having ordinary skill in the art.

[0019] Preferably, a foam is applied to the construction surface 10 forming a foam layer 12. The foam is preferably a polyurethane foam. Polyurethane foam is preferred because it can be easily sprayed in a controlled manner and remains tacky for an initial period after spraying. In addition, the period for which the foam remains tacky, or sticky, can be controlled by varying the composition of the foam. The foam may be sprayed onto the construction surface 10 and allowed to rise during a rise period.

[0020] As used herein, the term “rise period” refers to the period during which the foam, which is sprayed as a liquid, expands in volume as the result of the formation and expansion of gas bubbles in the liquid, as is well known by a person having ordinary skill in the art. The rise period ends when the foam ceases to expand, either because the gas-forming components are exhausted or because the polymerizing components of the foam become sufficiently rigid to prevent further expansion. At this point, the foam has cured. The rise of a foam can also be limited by confining the foam so that its expansion is limited, but this concept is not used in the present application. These techniques for controlling the properties of the foam after the rise period and for controlling the duration of the rise period are well known to a person having ordinary skill in the art.

[0021] After the foam rises, it forms a foam layer 12. The foam layer 12 is adjacent to the construction surface 10 at interface 14 forming an insulating and sealing barrier. The foam adheres to the construction surface 10 during the rise period, mechanically connecting the foam layer 12 to the construction surface 10.

[0022] The foam layer 12 may have various properties. The tack time of foams useful in the present invention can range from a few seconds to a few minutes. Because the insulating layer preferably adheres to the tacky foam, it has been found that foams having a tack time between 2 and 60 seconds, and more particularly between 10 and 20 seconds, are preferred for the present application. Furthermore, the rise and the density of the foam can be controlled, as is well known to a person having ordinary skill in the art. It has been found that foams having densities in the range of about 0.5 to about 3.5 pounds per cubic foot, more preferably from about 1 to about 2 pounds per cubic foot, and still more preferably from about 1.6 to about 1.8 pounds per cubic foot are preferred for the present application.

[0023] Additionally, while a foam layer 12 as thin as 0.25 inches or less will suffice to adhere an insulating bat 16 to the construction surface 10, it is preferred that the foam layer 12 be 0.5 to 1.5 and more preferably about 1 inch thick. Although a thicker foam layer 12 will provide more thermal insulation, because the ingredients of the foam are relatively expensive, it is currently economically preferred to construct the foam layer 12 such that it is less than 2 inches thick.

[0024] After application of the foam forming the foam layer 12 on the construction surface 10, an insulating material is applied to the foam layer 12. The insulating material may be a bat 16 of insulating material, as represented in FIG. 1. The bat 16 may be composed of glass fiber insulation, mineral wool insulation, or any other insulating material with desirable thermal properties and can include one or more outer layers of paper or other material. If the bat includes a layer of paper on one side, the insulation is preferably, but not necessarily, applied with the paper layer outward, so that the fibers of the insulation material contact the foam. The tackiness of the foam allows the bat 16 to adhere to the foam layer 12. The bat 16 is preferably applied such that the outer fibers of the insulating material contact the foam layer 12. The outer fibers of the bat 16 mix with the tacky foam layer 12, forming a boundary layer 18 where the outer fibers are mixed with the foam layer 12 and thereby causing the bat 16 to stick to the foam layer 12. Thus, a mechanical bond is formed between the foam layer 12 and the bat 16 such that the foam layer 12 supports the bat 16.

[0025] Formation of the mechanical bond may be improved by pressing the bat 16 as it is applied to the foam layer 12. Pressing the bat 16 will push more of the outer fibers of the bat 16 into the tacky outer surface of the foam layer 12, improving the rigid mechanical bond to further support the bat 16. Also, formation of the mechanical bond is improved by applying the bat 16 before the foam layer 12 has fully cured. Before the foam layer 12 has fully cured, the foam remains tacky and malleable, allowing the outer fibers of the bat 16 to be pressed into the boundary layer 18 of the foam layer 12, thus forming a stronger mechanical bond.

[0026] Because a moisture barrier is often desired, it is preferred to create a foam layer 12 that is continuous across the construction surface 10 that is to be insulated. If applied over substantially the entire construction surface 10, the foam layer 12 provides a sealing barrier preventing the ingress and egress of air and moisture and a layer of insulation impeding heat transfer through the construction surface 10. Optionally, as indicated in FIG. 2, an additional layer 20 can precede the foam layer 12, so long as it is securely fastened to the construction surface 10.

[0027] If a moisture barrier is not required, it is possible to support the bat 16 with a foam layer 12 that covers less than the entire construction surface 10. For example, as indicated in FIG. 3, foam can be sprayed such that there are some gaps between construction surface 10 and bat 16. The foam layer 12 may be applied around the periphery of the construction surface 10, in lines across the construction surface 10, or in dispersed spots on construction surface 10. Any pattern of application of the foam layer 12 on the construction surface 10 is acceptable, so long as the foam layer 12 contains a sufficient number of contact points such that the bat 16 of insulating material will be supported.

[0028] A further embodiment of the present invention provides an insulating structure. As can be seen with reference to FIG. 4, the structure consists of a building 24 or other enclosed space. The building 24 may be a residential structure containing a part that is normally uninhabited, such as an attic or storage area, or the building 24 may be any shelter that is not insulated or that contains a portion that is not insulated. The building 24 may consist of side walls 26 and 28, a floor 30, and a ceiling 32. The building 24 may be shaped as shown in FIG. 4, or it may consist of other shapes bounded by at least one wall that is not insulated. The building 24 may contain any number of rooms.

[0029] The building 24, as represented in FIG. 4, is insulated and sealed on at least one side wall 26 with the present invention. Although an exterior wall is shown as insulated in FIG. 4, the present invention may also be applied to an interior wall. Also, although a smooth inside surface of side wall 26 is depicted in FIG. 4, side wall 26 may be interrupted by structural members. A foam layer 12 is attached to the side wall 26. The foam layer 12 may provide insulation and sealing, or it may simply provide insulation. The foam layer 12 may cover the entire side wall 26 as shown in FIG. 4, or it may cover only a portion of side wall 26 sufficient to support the bat of insulating material 16. Additionally, an optional layer may be present between the foam layer 12 and the side wall 26 to provide sealing or thermal insulation, so long as the optional layer is mechanically coupled to the side wall 26 in a manner sufficient to support the weight of the foam layer 12 and the bat 16 of insulating material.

[0030] The foam layer 12 preferably consists of polyurethane foam. Polyurethane foam has favorable properties for use in this application because of the ease with which the properties may be adjusted. The preferences discussed above with respect to rise period, density, and thickness of the foam layer 12 are also applicable here. That is, most preferably, the foam layer 12 should have a rise period between 10 and 20 seconds, a density between 1.6 and 1.8 pounds per cubic foot after the rise period, and a thickness of about 1 inch after the rise period. Although the broader limits discussed above are also possible here, these limits represent the most preferable range of application.

[0031] A bat 16 of insulating material is attached to the foam layer 12. Although a bat 16 of insulating material is depicted in FIG. 4, other forms of insulating material may be suitable for attaching to foam layer 12, such as fiberboard insulation or spray insulation. Additionally, the bat 16 of insulating material may be composed of mineral wool insulation or glass fiber insulation, or any other insulating material having desirable insulating properties. Fibers from the bat 16 of insulating material are interwoven into the foam layer 12 mechanically coupling the bat 16 to the foam layer 12. The mechanical link provides support for the bat 16. The bat 16 provides further insulation to the side wall 26.

[0032] In the embodiment of FIG. 4, building 24 is insulated by applying an embodiment of the present invention to side wall 26. However, side wall 28, as well as floor 30 and ceiling 32, may also be insulated using an embodiment of the present invention. Additionally, side wall 26 may be only partially insulated and/or sealed using the present invention. Building 24 may be insulated and/or sealed by having the present invention applied to any portion or all of side walls 26 and 28, as well as floor 30 and ceiling 32. Building 24 may contain interior walls that may be insulated and/or sealed by having the present invention applied to them.

[0033] As can be seen from the preceding discussion, the present invention allows for rapid, economical and effective application of sealing and insulating layers to the inside wall, ceiling, and floor surfaces. The preceding discussion, however, is not to be taken as a complete description of all possible embodiments of the present invention. As will be apparent to one having ordinary skill in the art, the present invention is readily adaptable to many other embodiments. For example, the foam can be applied to either the construction surface 10 or to the outer surface of the bat 16; however, the former is preferred because it facilitates handling of the bat 16. Also, in some instances it may be desirable to pat or roll the outer surface of the bat 16 so as to enhance the mechanical bond that occurs at the interface 18 between the bat 16 and the foam layer 12. These and other improvements will be obvious to one having ordinary skill in the art. 

1. A method for insulating a construction surface comprising: (a) applying a foam to the construction surface such that a foam layer is formed on the construction surface; and (b) applying insulating material to said layer foam such that said insulating material engages said foam layer and is mechanically supported thereby.
 2. The method of claim 1, wherein step (a) comprises spraying a polyurethane foam.
 3. The method of claim 2, wherein said foam is a polyurethane foam having a tack time between 2 and 60 seconds.
 4. The method of claim 3, wherein said foam has a density after rising of between 0.5 and 3.5 pounds per cubic foot.
 5. The method of claim 4, wherein step (a) comprises spraying a polyurethane foam onto said construction surface such that said foam layer has a thickness after rising of between 0.25 and 2 inches.
 6. The method of claim 5, wherein said polyurethane foam has a tack time between 10 and 20 seconds.
 7. The method of claim 6, wherein said polyurethane foam has a density after rising of between 1 and 2 pounds per cubic foot.
 8. The method of claim 2, wherein step (b) comprises applying a bat of insulating material to said foam before said foam is fully cured.
 9. A method of insulating a construction surface comprising: (a) forming a foam layer on said construction surface; and (b) pressing an insulating material into engagement with said foam layer such that it mechanically couples to said foam layer.
 10. The method of claim 9, wherein step (a) comprises forming a polyurethane foam layer.
 11. The method of claim 10, wherein said foam layer is a polyurethane foam layer having a tack time between 2 and 60 seconds.
 12. The method of claim 11, wherein step (b) comprises pressing said insulating material into engagement with said foam layer before said foam layer has fully cured.
 13. The method of claim 9, wherein step (b) comprises pressing a bat of insulating material into engagement with said foam layer before said foam layer is fully cured.
 14. The method of claim 13, wherein said foam layer comprises a polyurethane foam layer having a thickness between 0.25 and 2 inches.
 15. The method of claim 14, wherein said polyurethane foam layer has a density after rising between 1 and 2 pounds per cubic foot.
 16. The method of claim 15, wherein said polyurethane foam layer has a tack time between 10 and 20 seconds.
 17. A method for sealing a construction surface comprising: (a) applying a polyurethane foam to said construction surface such that a foam layer is formed on said construction surface, said foam layer substantially sealing said construction surface.
 18. The method of claim 17 further comprising: (b) engaging a bat of insulating material with said foam layer such that said bat of insulating material is mechanically coupled to said foam layer.
 19. The method of claim 18, wherein step (a) comprises applying a polyurethane foam to said construction surface such that a foam layer is formed having a tack time between 2 and 60 seconds.
 20. The method of claim 19, wherein step (a) further comprises applying a polyurethane foam to said construction surface such that a foam layer is formed having a thickness after rising between 0.25 and 2 inches.
 21. The method of claim 20, wherein step (a) further comprises applying a polyurethane foam to said construction surface such that a foam layer is formed having a density after rising of between 0.5 and 3.5 pounds per cubic foot.
 22. The method of claim 19, wherein step (b) comprises applying a bat of insulating material to said foam layer before said foam layer is fully cured.
 23. The method of claim 22, wherein said bat of insulating material comprises fiberglass insulating material.
 24. The method of claim 22, wherein said bat of insulating material comprises mineral wool insulating material.
 25. A building comprising: (a) a construction surface comprising a side; (b) a polyurethane foam layer adjacent to said side of said construction surface and mechanically coupled to said construction surface; and (c) an insulating layer mechanically coupled to said foam layer.
 26. The building of claim 25, wherein said polyurethane foam layer has a thickness between 0.25 and 2 inches.
 27. The building of claim 26, wherein said polyurethane foam layer has a density between 0.5 and 3.5 pounds per cubic foot.
 28. The building of claim 27, wherein said thickness is between 0.5 and 1.5 inches.
 29. The building of claim 28, wherein said density is between 1 and 2 pounds per cubic foot.
 30. The building of claim 25, wherein said polyurethane foam layer has a tack time and wherein said insulating layer is mechanically coupled to said polyurethane foam layer by applying said insulating layer before said polyurethane foam layer is fully cured.
 31. The building of claim 30, wherein said tack time is between 2 and 60 seconds.
 32. The building of claim 31, wherein said tack time is between 10 and 20 seconds.
 33. The building of claim 30, wherein said insulating layer comprises glass fiber insulation.
 34. The building of claim 30, wherein said insulating layer comprises mineral wool insulation. 